Log Strike Test System designed by student in Sweden: Fredrik Helgesson
A college student in Sweden, Fredrik Helgesson, designed a test stand to log strike test outboard motors (outboard motors impact floating logs).
The report is titled, Konstruktion av “log strike”-testrigg for utomboardsmotorer.
Back in early 2016 Mr. Helgesson, a mechanical engineering student at Halmstad University in Sweden, contacted us a few times for technical specifications on how the industry tests log strike systems. He said he was working on a thesis focused on that topic. We supplied him several publicly available materials, some thoughts on the topic, and told him that if he was not teamed with one of the major outboard manufacturers he would likely not have access to the exact specifications manufacturers use for log strike testing.
A couple months ago we noticed his paper had been published by Halmstad University.
We then learned his project was more of a design project teamed with a manufacturer of diesel outboards, Cimco Marine AB>.
The cover of the report is shown below. Click on it to view the full pdf report.
The report is in Swedish with portions in English. It can be translated a few pages at a time using Google Translate.
An English abstract is available in the report and on Diva.
His design resembles that of the stand used by Mercury Marine. He uses hydraulic rams to propel something into the stationary drive.
The report includes his design calculations and briefly talks about me and PropellerSafety.com .
We salute Mr. Helgesson for carrying out this project and Cimco for recognizing the need to test their outboards. However, if Mr. Helgesson had voiced his intentions (design an economical test stand for a low volume diesel outboard manufacturer), we could have suggested some more basic approaches.